Communication systems of various kinds, including but not limited to wireless communication systems, are known in the art. In many such systems, some or all of the users are afforded, to a greater or lesser extent, a degree of privacy with respect to their communications. For example, both technical and legal means are often employed to seek to discourage and/or prohibit eavesdropping on the conversations of such a communication system user. Notwithstanding such efforts, however, unauthorized individuals and/or organizations continue to attempt to breach and/or evade such protective measures.
Pursuant to one approach, the unauthorized individual employs a so-called cloned station to facilitate their eavesdropping. A cloned station typically comprises a mobile station that is otherwise compatible with the protocol requirements of a given communication system and that is further programmed to present the same Electronic Serial Number (ESN) and/or Mobile Identification Number (MIN) as another target platform that comprises the eavesdropping subject of interest.
Methods and apparatus exist to aid in detecting and/or preventing the successful use of cloned stations in a given communication system. Cloned station detection, however, can comprise a challenge in at least some systems. For example, in a code division multiple access (CDMA) communication system, a base station may consider transmissions as emanate from a cloned station to be merely a multi-path component of the transmissions of a legitimate authorized user (this can occur, at least in part, because both the authorized station and the cloned station will use an identical reverse link spreading code when accessing the communication system via standard signaling messages and procedures that rely greatly on ESN and MIN values to facilitation transmission source differentiation).
Authentication and/or voice privacy techniques could of course be employed to attempt to address this situation. Unfortunately, such solutions tend to require one or more additional implementing network elements and a corresponding development of corresponding facilitating features. These approaches would therefore tend to add considerable cost to the deployment of a given communication system. Those skilled in the art will further appreciate that such approaches may present considerable challenges when retroactively deployed.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein.